1 /*****************************************************************************
2 * input_ext-dec.h: structures exported to the VideoLAN decoders
3 *****************************************************************************
4 * Copyright (C) 1999-2001 VideoLAN
5 * $Id: input_ext-dec.h,v 1.80 2003/09/02 20:19:25 gbazin Exp $
7 * Authors: Christophe Massiot <massiot@via.ecp.fr>
8 * Michel Kaempf <maxx@via.ecp.fr>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
23 *****************************************************************************/
25 #ifndef _VLC_INPUT_EXT_DEC_H
26 #define _VLC_INPUT_EXT_DEC_H 1
28 /* Structures exported to the decoders */
30 /*****************************************************************************
32 *****************************************************************************
33 * Describe a data packet.
34 *****************************************************************************/
37 /* Used to chain the packets that carry data for a same PES or PSI */
38 data_packet_t * p_next;
40 /* start of the PS or TS packet */
41 byte_t * p_demux_start;
42 /* start of the PES payload in this packet */
43 byte_t * p_payload_start;
44 byte_t * p_payload_end; /* guess ? :-) */
45 /* is the packet messed up ? */
46 vlc_bool_t b_discard_payload;
48 /* pointer to the real data */
49 data_buffer_t * p_buffer;
52 /*****************************************************************************
54 *****************************************************************************
55 * Describes an PES packet, with its properties, and pointers to the TS packets
57 *****************************************************************************/
60 /* Chained list to the next PES packet (depending on the context) */
61 pes_packet_t * p_next;
64 vlc_bool_t b_data_alignment; /* used to find the beginning of
65 * a video or audio unit */
66 vlc_bool_t b_discontinuity; /* This packet doesn't follow the
69 mtime_t i_pts; /* PTS for this packet (zero if unset) */
70 mtime_t i_dts; /* DTS for this packet (zero if unset) */
71 int i_rate; /* current reading pace (see stream_control.h) */
73 unsigned int i_pes_size; /* size of the current PES packet */
75 /* Chained list to packets */
76 data_packet_t * p_first; /* The first packet contained by this
77 * PES (used by decoders). */
78 data_packet_t * p_last; /* The last packet contained by this
79 * PES (used by the buffer allocator) */
80 unsigned int i_nb_data; /* Number of data packets in the chained list */
83 /*****************************************************************************
85 *****************************************************************************
86 * This rotative FIFO contains PES packets that are to be decoded.
87 *****************************************************************************/
92 /* Thread structures */
93 vlc_mutex_t data_lock; /* fifo data lock */
94 vlc_cond_t data_wait; /* fifo data conditional variable */
97 pes_packet_t * p_first;
98 pes_packet_t ** pp_last;
99 int i_depth; /* number of PES packets in the stack */
101 /* Communication interface between input and decoders */
102 input_buffers_t *p_packets_mgt; /* packets management services data */
104 /* Standard pointers given to the decoders as a toolbox. */
106 vlc_fourcc_t i_fourcc;
107 es_sys_t * p_demux_data;
108 stream_ctrl_t * p_stream_ctrl;
109 sout_instance_t * p_sout;
110 void * p_waveformatex;
111 void * p_bitmapinfoheader;
116 /*****************************************************************************
118 *****************************************************************************
119 * The decoder descriptor.
120 *****************************************************************************/
125 /* Module properties */
127 decoder_sys_t * p_sys;
128 int ( * pf_init ) ( decoder_t * );
129 int ( * pf_decode )( decoder_t *, block_t * );
130 int ( * pf_end ) ( decoder_t * );
132 /* Input properties */
133 decoder_fifo_t * p_fifo; /* stores the PES stream data */
135 /* Tmp field for old decoder api */
136 int ( * pf_run ) ( decoder_fifo_t * );
139 /*****************************************************************************
140 * bit_fifo_t : bit fifo descriptor
141 *****************************************************************************
142 * This type describes a bit fifo used to store bits while working with the
143 * input stream at the bit level.
144 *****************************************************************************/
145 typedef uint32_t WORD_TYPE;
147 typedef struct bit_fifo_t
149 /* This unsigned integer allows us to work at the bit level. This buffer
150 * can contain 32 bits, and the used space can be found on the MSb's side
151 * and the available space on the LSb's side. */
154 /* Number of bits available in the bit buffer */
159 /*****************************************************************************
160 * bit_stream_t : bit stream descriptor
161 *****************************************************************************
162 * This type, based on a PES stream, includes all the structures needed to
163 * handle the input stream like a bit stream.
164 *****************************************************************************/
175 /* The decoder fifo contains the data of the PES stream */
176 decoder_fifo_t * p_decoder_fifo;
178 /* Callback to the decoder used when changing data packets ; set
179 * to NULL if your decoder doesn't need it. */
180 void (* pf_bitstream_callback)( bit_stream_t *, vlc_bool_t );
181 /* Optional argument to the callback */
182 void * p_callback_arg;
187 mtime_t i_pts, i_dts;
188 byte_t * p_pts_validity;
193 /* Current PES packet (extracted from the PES stream) */
194 pes_packet_t * p_pes;
195 /* Current data packet (in the current PES packet) */
196 data_packet_t * p_data;
197 /* Pointer to the next byte that is to be read (in the current packet) */
199 /* Pointer to the last byte that is to be read (in the current packet */
201 /* Temporary buffer in case we're not aligned when changing data packets */
202 WORD_TYPE i_showbits_buffer;
203 data_packet_t showbits_data;
206 /*****************************************************************************
207 * Inline functions used by the decoders to read bit_stream_t
208 *****************************************************************************/
211 * DISCUSSION : How to use the bit_stream structures
213 * sizeof(WORD_TYPE) (usually 32) bits are read at the same time, thus
214 * minimizing the number of p_byte changes.
215 * Bits are read via GetBits() or ShowBits.
217 * XXX : Be aware that if, in the forthcoming functions, i_bits > 24,
218 * the data have to be already aligned on an 8-bit boundary, or wrong
219 * results will be returned. Use RealignBits() if unsure.
222 #if (WORD_TYPE == uint32_t)
223 # define WORD_AT U32_AT
224 # define WORD_SIGNED int32_t
225 #elif (WORD_TYPE == uint64_t)
226 # define WORD_AT U64_AT
227 # define WORD_SIGNED int64_t
229 # error Unsupported WORD_TYPE
232 /*****************************************************************************
233 * Prototypes from input_ext-dec.c
234 *****************************************************************************/
235 VLC_EXPORT( void, input_ExtractPES, ( decoder_fifo_t *, pes_packet_t ** ) );
236 VLC_EXPORT( void, input_DeletePES, ( input_buffers_t *, pes_packet_t * ) );
237 VLC_EXPORT( int, InitBitstream, ( bit_stream_t *, decoder_fifo_t *, void ( * )( bit_stream_t *, vlc_bool_t ), void * p_callback_arg ) );
238 VLC_EXPORT( vlc_bool_t, NextDataPacket, ( decoder_fifo_t *, bit_stream_t * ) );
239 VLC_EXPORT( void, BitstreamNextDataPacket, ( bit_stream_t * ) );
240 VLC_EXPORT( uint32_t, UnalignedShowBits, ( bit_stream_t *, unsigned int ) );
241 VLC_EXPORT( void, UnalignedRemoveBits, ( bit_stream_t * ) );
242 VLC_EXPORT( uint32_t, UnalignedGetBits, ( bit_stream_t *, unsigned int ) );
243 VLC_EXPORT( void, CloseBitstream, ( bit_stream_t * ) );
244 VLC_EXPORT( void, CurrentPTS, ( bit_stream_t *, mtime_t *, mtime_t * ) );
245 VLC_EXPORT( void, NextPTS, ( bit_stream_t *, mtime_t *, mtime_t * ) );
247 /*****************************************************************************
248 * AlignWord : fill in the bit buffer so that the byte pointer be aligned
249 * on a word boundary (XXX: there must be at least sizeof(WORD_TYPE) - 1
250 * empty bytes in the bit buffer)
251 *****************************************************************************/
252 static inline void AlignWord( bit_stream_t * p_bit_stream )
254 while( (ptrdiff_t)p_bit_stream->p_byte
255 & (sizeof(WORD_TYPE) - 1) )
257 if( p_bit_stream->p_byte < p_bit_stream->p_end )
259 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
260 << (8 * sizeof(WORD_TYPE) - 8
261 - p_bit_stream->fifo.i_available);
262 p_bit_stream->fifo.i_available += 8;
266 BitstreamNextDataPacket( p_bit_stream );
267 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
268 << (8 * sizeof(WORD_TYPE) - 8
269 - p_bit_stream->fifo.i_available);
270 p_bit_stream->fifo.i_available += 8;
275 /*****************************************************************************
276 * ShowBits : return i_bits bits from the bit stream
277 *****************************************************************************/
278 static inline uint32_t ShowBits( bit_stream_t * p_bit_stream,
279 unsigned int i_bits )
281 if( (unsigned int)p_bit_stream->fifo.i_available >= i_bits )
283 return( p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits) );
286 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
288 return( (p_bit_stream->fifo.buffer |
289 (WORD_AT( p_bit_stream->p_byte )
290 >> p_bit_stream->fifo.i_available))
291 >> (8 * sizeof(WORD_TYPE) - i_bits) );
294 return( UnalignedShowBits( p_bit_stream, i_bits ) );
297 /*****************************************************************************
298 * ShowSignedBits : return i_bits bits from the bit stream, using signed
300 *****************************************************************************/
301 static inline int32_t ShowSignedBits( bit_stream_t * p_bit_stream,
302 unsigned int i_bits )
304 if( (unsigned int)p_bit_stream->fifo.i_available >= i_bits )
306 return( (WORD_SIGNED)p_bit_stream->fifo.buffer
307 >> (8 * sizeof(WORD_TYPE) - i_bits) );
310 /* You can probably do something a little faster, but now I'm tired. */
311 return( (WORD_SIGNED)(ShowBits( p_bit_stream, i_bits ) << (32 - i_bits))
315 /*****************************************************************************
316 * RemoveBits : removes i_bits bits from the bit buffer
317 * XXX: do not use for 32 bits, see RemoveBits32
318 *****************************************************************************/
319 static inline void RemoveBits( bit_stream_t * p_bit_stream,
320 unsigned int i_bits )
322 p_bit_stream->fifo.i_available -= i_bits;
324 if( p_bit_stream->fifo.i_available >= 0 )
326 p_bit_stream->fifo.buffer <<= i_bits;
330 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
332 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
333 << ( -p_bit_stream->fifo.i_available );
334 p_bit_stream->p_byte =
335 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
336 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
340 UnalignedRemoveBits( p_bit_stream );
343 /*****************************************************************************
344 * RemoveBits32 : removes 32 bits from the bit buffer (and as a side effect,
346 *****************************************************************************/
347 #if (WORD_TYPE == uint32_t)
348 static inline void RemoveBits32( bit_stream_t * p_bit_stream )
350 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
352 if( p_bit_stream->fifo.i_available )
354 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
355 << (32 - p_bit_stream->fifo.i_available);
356 p_bit_stream->p_byte =
357 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
361 p_bit_stream->p_byte =
362 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
366 p_bit_stream->fifo.i_available -= 32;
367 UnalignedRemoveBits( p_bit_stream );
370 # define RemoveBits32( p_bit_stream ) RemoveBits( p_bit_stream, 32 )
373 /*****************************************************************************
374 * GetBits : returns i_bits bits from the bit stream and removes them
375 * XXX: do not use for 32 bits, see GetBits32
376 *****************************************************************************/
377 static inline uint32_t GetBits( bit_stream_t * p_bit_stream,
378 unsigned int i_bits )
382 p_bit_stream->fifo.i_available -= i_bits;
384 if( p_bit_stream->fifo.i_available >= 0 )
386 i_result = p_bit_stream->fifo.buffer
387 >> (8 * sizeof(WORD_TYPE) - i_bits);
388 p_bit_stream->fifo.buffer <<= i_bits;
392 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
394 i_result = p_bit_stream->fifo.buffer
395 >> (8 * sizeof(WORD_TYPE) - i_bits);
396 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
397 p_bit_stream->p_byte =
398 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
399 i_result |= p_bit_stream->fifo.buffer
400 >> (8 * sizeof(WORD_TYPE)
401 + p_bit_stream->fifo.i_available);
402 p_bit_stream->fifo.buffer <<= ( -p_bit_stream->fifo.i_available );
403 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
407 return UnalignedGetBits( p_bit_stream, i_bits );
410 /*****************************************************************************
411 * GetSignedBits : returns i_bits bits from the bit stream and removes them,
412 * using signed arithmetic
413 * XXX: do not use for 32 bits
414 *****************************************************************************/
415 static inline int32_t GetSignedBits( bit_stream_t * p_bit_stream,
416 unsigned int i_bits )
418 if( (unsigned int)p_bit_stream->fifo.i_available >= i_bits )
422 p_bit_stream->fifo.i_available -= i_bits;
423 i_result = (WORD_SIGNED)p_bit_stream->fifo.buffer
424 >> (8 * sizeof(WORD_TYPE) - i_bits);
425 p_bit_stream->fifo.buffer <<= i_bits;
429 /* You can probably do something a little faster, but now I'm tired. */
430 return( (WORD_SIGNED)(GetBits( p_bit_stream, i_bits ) << (32 - i_bits))
434 /*****************************************************************************
435 * GetBits32 : returns 32 bits from the bit stream and removes them
436 *****************************************************************************/
437 #if (WORD_TYPE == uint32_t)
438 static inline uint32_t GetBits32( bit_stream_t * p_bit_stream )
442 if( p_bit_stream->fifo.i_available == 32 )
444 p_bit_stream->fifo.i_available = 0;
445 i_result = p_bit_stream->fifo.buffer;
446 p_bit_stream->fifo.buffer = 0;
450 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
452 if( p_bit_stream->fifo.i_available )
454 i_result = p_bit_stream->fifo.buffer;
455 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
456 p_bit_stream->p_byte =
457 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
458 i_result |= p_bit_stream->fifo.buffer
459 >> (p_bit_stream->fifo.i_available);
460 p_bit_stream->fifo.buffer <<= (32 - p_bit_stream->fifo.i_available);
464 i_result = WORD_AT( p_bit_stream->p_byte );
465 p_bit_stream->p_byte =
466 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
470 p_bit_stream->fifo.i_available -= 32;
471 return UnalignedGetBits( p_bit_stream, 32 );
474 # define GetBits32( p_bit_stream ) GetBits( p_bit_stream, 32 )
477 /*****************************************************************************
478 * RealignBits : realigns the bit buffer on an 8-bit boundary
479 *****************************************************************************/
480 static inline void RealignBits( bit_stream_t * p_bit_stream )
482 p_bit_stream->fifo.buffer <<= (p_bit_stream->fifo.i_available & 0x7);
483 p_bit_stream->fifo.i_available &= ~0x7;
487 /*****************************************************************************
488 * GetChunk : reads a large chunk of data
489 *****************************************************************************
490 * The position in the stream must be byte-aligned, if unsure call
491 * RealignBits(). p_buffer must point to a buffer at least as big as i_buf_len
492 * otherwise your code will crash.
493 *****************************************************************************/
494 static inline void GetChunk( bit_stream_t * p_bit_stream,
495 byte_t * p_buffer, size_t i_buf_len )
497 ptrdiff_t i_available;
499 /* We need to take care because i_buf_len may be < 4. */
500 while( p_bit_stream->fifo.i_available > 0 && i_buf_len )
502 *p_buffer = p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - 8);
505 p_bit_stream->fifo.buffer <<= 8;
506 p_bit_stream->fifo.i_available -= 8;
509 i_available = p_bit_stream->p_end - p_bit_stream->p_byte;
510 if( i_available >= (ptrdiff_t)i_buf_len )
512 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
513 p_bit_stream->p_byte, i_buf_len );
514 p_bit_stream->p_byte += i_buf_len;
520 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
521 p_bit_stream->p_byte, i_available );
522 p_bit_stream->p_byte = p_bit_stream->p_end;
523 p_buffer += i_available;
524 i_buf_len -= i_available;
525 BitstreamNextDataPacket( p_bit_stream );
526 if( p_bit_stream->p_decoder_fifo->b_die )
529 while( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
530 <= (ptrdiff_t)i_buf_len );
534 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
535 p_bit_stream->p_byte, i_buf_len );
536 p_bit_stream->p_byte += i_buf_len;
540 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
542 AlignWord( p_bit_stream );
548 * Communication interface between input and decoders
551 /*****************************************************************************
552 * Prototypes from input_dec.c
553 *****************************************************************************/
554 VLC_EXPORT( void, DecoderError, ( decoder_fifo_t * p_fifo ) );
556 #endif /* "input_ext-dec.h" */